I have backing plates, sort of a large SS square fender washer, for each bolt. But it looks like both of our boats are very similar.

I am getting the same idea, "...have them mirror polished, to ensure long life." IF I do go back with SS I will just put them on my scheduled replacement list. And pick what I think is a good number. The same way they do on a lot of parts in aircraft maintenance, life rafts and other stuff.

Greg